The USB specifications provide for 500mA on USB 2.0 ports and 900mA for USB 3.0 ports - and this is what you should expect to see on the NUC's internal (black) USB 2.0 ports and external (blue) USB 3.0 ports. The USB Charging specification provides for 1500mA (1.5A) on USB 3.0 Charging ports - and this is what you should expect to see, at a minimum, on the NUC's external (yellow) USB 3.0 Charging port. This port is actually fused for 2000mA, so it's possible you may get more than 1500mA.